Connor can be heard moaning in the background as his friend repeats: “Please, please hurry up.”

Will Blencowe, who admits stabbing the youth but denies his murder, held his head in his hands as he listened to the phone call.

The recording was played yesterday in Oxford Crown Court on day two of his trial, at the end of the prosecution’s opening speech.

Earlier prosecutor Richard Barton told the jury Blencowe did not deny being responsible for Connor’s injuries, which led to his death in the John Radcliffe Hospital two days later.

But he said the 21-year-old will argue he has “diminished responsibility” because he was suffering from a mental condition and was also acting in self defence.

Mr Barton told the jury they will have to decide if this is true or if really it was “a planned murderous act, in which (Blencowe) remained in control throughout”.

The prosecution’s case is that the defendant murdered his teenage victim because he was jealous that Connor was seeing his ex-girlfriend Aimee Harrison.

Giving evidence yesterday, Miss Harrison, 20, said after Blencowe ended their relationship she was briefly “intimate” with a man called Ben Harris.

She said this led to Blencowe, of Oxford Road, Banbury, attacking Mr Harris at the Bitter and Twisted pub in Chipping Norton in October last year.

Miss Harrison said: “When I told him he went crazy on the phone. He got a taxi to Chipping Norton to beat Ben up.

“I was there and I tried to stop him going into the pub because I knew what he was like and he had a knuckle duster.”

She said Blencowe punched and tried to knee Mr Harris and also took a swing at the pub’s manager.

Miss Harrison added: “Me and Connor didn’t want people knowing about us after the way (Blencowe) reacted with Ben. We didn’t know if he would be the same and we really didn’t want that.”

But Blencowe’s barrister Adrian Amer suggested his client only became angry at Mr Harris because Miss Harrison said he had forced himself on her.

The witness denied she ever said this and also denied telling Connor that Blencowe was a “psychopath” to scare him and wind him up.

Bradley Jones, 21, of New Road, Bledington, and Grant Clemens, 23, of Stockwells, Moreton-in-Marsh, are also on trial and both deny perverting the course of justice.

Mr Barton said when he was arrested Blencowe was wearing trainers and clothes given to him by Clemens, who was also overheard by a police officer after his own arrest telling his girlfriend to destroy his mobile phone.

He added that Jones was with Blencowe during the assault on Mr Harris inside the pub and did not stop what happened.

This was disputed by Jones’s barrister Graham Logan, who said he tried to restrain Blencowe.

The trial continues.

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